The present invention is directed to the field of weaponry. More particularly, the present invention is directed to an action breech assembly for a muzzle-loaded rifle.
The present invention remedies a number of issues which have arisen regarding Applicant's earlier U.S. Pat. No. 5,722,193 issued Mar. 3, 1998. More specifically, the features of the present invention improve/simplify manufacture, operation, cleanability of the earlier mechanism as well as providing a sizing die for enhancing performance of the muzzle-loaded rifle by providing ammunition which has been sized to fit in the bore of a particular rifle barrel.
The action breech assembly of the present invention comprises a) a pivot block pinned to a barrel breech, the pivot block having fixed thereto a pivot pin and a plunger stop pin laterally offset from the pivot pin; b) a one-piece action housing including i) hook means for suspending the action housing on the pivot pin, the hook means having an opening on one side thereof; ii) a retractable thumb release assembly, the release assembly including a sliding arm partially closing the opening to maintain the one piece action housing suspended from the pivot pin; iii) a cocking plunger assembly slidably mounted in the one-piece action housing, the cocking plunger assembly having an aft action end, a hook engaged over the plunger stop pin; iv) a striker assembly reciprocally mounted in the one-piece housing, the striker assembly including α) a generally cylindrical striker element having a forward-facing shoulder engagable by the aft action end of the cocking plunger; β) a recess extending from an aft end of the generally cylindrical striker element through a significant portion of its length; γ) a main spring assembly extending into the recess and engaging a forward surface of the recess; c) a primer adapter angulated through the pivot block for seating a primer; whereby when the one-piece action housing is rotated about the pivot pin from an at rest position to an open, cocking position, the lateral offset between the pivot pin and the plunger stop pin causes the cocking plunger assembly to move the striker assembly rearwardly and uncovers the primer adapter providing access thereto.
The breech assembly has a peripheral groove in a surface of the generally cylindrical striker element, and a pivoting sear link having a projection extending upwardly into the groove to retain the striker assembly in a cocked position. A cross bolt safety member is at least partially positionable beneath the pivoting sear link to inhibit its movement thereby preventing reciprocal movement of the striker assembly.
A trigger assembly includes a) a J-shaped trigger element; b) a pivot pin securing the trigger element to the one-piece action housing; c) a trigger force plunger engaging an upper arm of the J-shaped trigger; d) a spring exerting a downward pressure on the trigger force plunger; e) an adjustable set screw engaging an upper portion of the spring facilitating simple adjustment of the downward pressure on the trigger force plunger. A transfer pin extends between a forward end of the trigger element and a rear end of the pivoting sear link whereby when the trigger element pivots about the pivot pin, the transfer pin causes the pivoting sear link to rotate downwardly disengaging the projection from the groove allowing the main spring to propel the striker assembly forward.
The action breech assembly includes a breech plug into which the primer adapter extends, and a removable orifice seal module insertable into the barrel breech immediately downstream of the breech plug. The orifice seal module defines a first end of a powder chamber of the breech and further comprises a replaceable throat bushing at a second opposite end of the powder chamber which prevents the bullet from entering the powder chamber. The action breech assembly has over-pressure vent means for preventing damage to the barrel breech. Preferably, the over-pressure vent means includes a thin-flanged plug inserted into a wall portion of the barrel breech. Alternatively, the over-pressure vent means is a vent hole in the barrel breech and a thin wall portion of the orifice seal module which covers the vent hole.
The action breech assembly features a leaf spring attached to a rear portion of the breech assembly and extending downwardly to engage a rear portion of the one-piece action housing to retain the one-piece action housing in the at rest position. A screw head extends from the rear portion of the breech assembly, the leaf spring having a hole which receives the screw head to retain the one-piece action housing in the at rest position. An arcuate extension for finger engagement on the leaf spring for release thereof from the screw head allows the one-piece action housing to move to the open, cocked position.
The invention additionally includes an adjustable sizing die assembly for shaping a bullet, the sizing die assembly comprising a) a cylindrical steel sizing die having a first external diameter and a through bore with an internal diameter generally equivalent to an external diameter of a bullet which may be either smooth bored or the bore may include rifling grooves, the cylindrical steel sizing die having a first thin-walled tapering portion formed on a first end; b) an external sleeve having a first internal diameter equivalent to the first external diameter of the cylindrical steel sizing die and a second internal diameter larger than the first internal diameter, the second internal diameter being threaded; c) a female compression collar having a first length with a uniform internal diameter, a second length having an internal taper configured to receive the first thin-walled tapering portion, and an external thread which mates with the second internal diameter of the external sleeve; whereby when the female compression collar is tightened into the second internal diameter, the second length having the internal taper collapses the first thin-walled tapering portion to a smaller effective diameter such that when a bullet is pushed through said sizing die assembly, the bullet is swaged down to a proper diameter, size and form. The die assembly may include rifling grooves etched into the internal through bore whereby forcing the bullet through said sizing die assembly also causes the rifling grooves to be transferred to the external diameter of the bullet.
Various other features, advantages, and characteristics of the present invention will become apparent after a reading of the following detailed description.